We would like to do another column on the topic of drumlins. These are little ice age hills which were sculpted by the advancing glaciers of about 14,000 years ago. Theories vary considerably but most geologists argue that ice sculpted coarse sediments into the shape of an upside down spoon bowl. They are striking features when viewed from the ground or air; once you have learned to recognize them, you will be surprised at how many there are. We have long marveled at how many drumlins there are in the Mohawk and Hudson Valleys. New York State is renowned for this. The fact is that the lion’s share of the world’s drumlins is found in our state. Makes you swell with regional pride, doesn’t it? Well, it should.

Map of Columbia County showing locations of drumlins. Hudson River on left.

Seeing them from the ground is something that we will explore again, sometime in the future, but today we want to work from a graphic. It’s from our book “The Hudson Valley in the Ice Age. It’s adapted from the New York Geological Survey topographic maps of our region, and it shows just how important drumlins are in our region. We can learn to appreciate what they represent, and the history they speak to us of.

Picture of a drumlin.

Our map shows a host of drumlins. Each oval represents a single occurrence and we count 120 or so of them; there are probably more. Each oval is parallel with long axis its drumlin and that records the direction of the glacier’s flow. Collectively they record the passage of a glacier that, though big, wasn’t as large as some earlier ones. It was just small enough to be channeled by the valley. You can “see” its flow from the drumlins. Most of the motion is due south, but some of the ice veered to the southeast. Everything is near the bottom of the Hudson Valley. Let’s call it the Hudson Valley glacier.

Though big, we are uncertain of its full extent. The many drumlins we see on the map cover all of Glacial Lake Albany and stretch a little beyond it to the east. Evidently, the ice had little difficulty moving across the old lake bottom. The landscape here was smooth and flat and offered little to block the flow. To the east the landscape is a little more elevated, and the ice only pressed a short distance that way. Thus the ice was essentially confined to the Hudson Valley. The glacier evidently thinned to the south. Around Kinderhook, drumlins reach elevations up to 650 feet. That drops to between 200 and 300 around Clermont.

You can understand why geologists get excited about this sort of thing. With maps like these we can closely document the last stages in the great glaciation that brought the ice age to an end in our region. Our drumlins bring the ice to life and graphically speak to us of what the glaciers were doing.

And our story has a lot of detail to it. The ice had previously retreated to somewhere in the north. This had left behind Glacial Lake Albany which filled most of the Hudson Valley. But the drumlins are features that lie on top of the lake beds; they must be younger. That means there had been one last readvance. When, exactly, this happened we cannot say with precision. The advance came after the time of the lake, but how many years later we do not know, probably not many.

We are forced to depend on our imaginations a little here, at least until better evidence turns up. It is quite possible that the lake was still there as the ice advanced. It would be easy for the ice to “skate” across the frozen lake. That would account for its apparent confinement to the lake area. Other geologists date it to a bit earlier than that glacial advance.

Remember the last time you skated upon a large pond, or better, on a large lake. Now, in your mind’s eye, look north and watch as a glacier is moving slowly toward you. It’s quite a vision and it may well have happened right around here.

This column likes to get you out and take you to places you have not been before. Summer is coming up and it is nice to wander about and maybe learn a little geology along the way. How about Conesville in Schoharie County? How many of you have been there? It’s a very rural little village in the heart of the Catskills. It’s just east of Gilboa; does that help? The main highway of Conesville is Potter Mountain Road and that takes you down the valley of the Manor Kill which is a tributary of the Schoharie Creek. The area is a bit of a backwater today, but it seems to have had a more prominent past.

The road must have once been of some importance. You pass the ancient Richtmyer Tavern which, although long closed, looks like it was once a busy hostelry along a busy highway. There’s not much traffic today. This was once farmland and probably pretty good farming occurred here. Nowadays you will see some cattle but not much more. Maybe this is no cosmopolitan center, but there is a lot of past here, and I was eager to explore it, not the historic past, the deep past of its geology.

The Richtmyer Tavern

I commonly enter the valley from the east. When I saw it for the first time, I recognized it for what it is – geologically – the bottom of an Ice Age lake. If you drive the road and pay heed to the valley you will see how flat and wide it all is. That’s typical of any lake bottom; they mostly tend to be very flat. Lake sediments pile up as strata of flat sheets of clay and silt, hence the flat bottom.

Floor of Lake Conesville – from east end of lake.

It’s the size that impresses you the most; this was a big lake: about two miles long and a half mile across. There is a gentle slope to the west. That is towards the lake’s old outlet which, in turn, led toward the Schoharie Creek Valley.

If you travel down the valley about two miles to the west, you will suddenly see that things change. The valley walls close in and the broad open expanse of the valley disappears. Here the Manor Kill becomes confined to what is almost a canyon. Small hills crowd in on both sides. We have reached the end of the old lake.

I slowed down along this stretch of the road; I was curious to understand what was here. My best judgment was that this is an old Ice Age moraine. I had better explain what that is. A moraine is a heap of coarse earth that was mostly bulldozed in place by an advancing glacier. I was guessing that once, long ago, coming from the Schoharie Valley and heading to the ea st, there had been a sizable valley glacier. It advanced along this part of the Manor Kill and then came to a halt. At this moment it left behind that heap of earth. Such a glacier shoves enormous amounts of earth before it. Even more sediment is carried within the ice, and that contributes to the total. The result is the moraine, a big mass of very heterogeneous sediment, clogging the whole of the valley.

The moraine made up an earthen dam which accounts for the presence of this lake. That blocked the valley here and water backed up east of it to form the lake. I looked at all this and then turned around to look back to the east. In my mind’s eye I could see the old lake. I had picked a quiet overcast day, roughly 14,000 years ago. The lake waters were still, dark, and black. All along the shores there were shelves of ice sticking out, but the middle was clear water. It was unbelievably silent all around me; this was a nearly lifeless world. It was still, after all, the Ice Age. But, in the far distance, back the lake’s full two miles, I could hear a powerful current flowing into the lake.

The current flowed through the lake, reaching out to its western end. Now I turned around again and looked west. That current was pouring through the canyon, creating a very loud, even violent torrent. It was this rush of water that had eroded the canyon. Time speeded up for me and that canyon was being cut down deeper and deeper. Gradually it came to be lowered until the dam was gone. All the water of the lake slowly and gradually drained out of it. The now dry lake bottom began to take on its modern form. It began to resemble the valley I had known. Now I truly understood what I was looking at.

Contact the author at titusr@hartwick.edu or visit his facebook page, “The Catskill Geologist.” Robert and Johanna Titus are now writing columns for The Mountain Eagle.

If you have been reading our columns long enough, then you know how fond we are of the 19th century Hudson River School of Landscape Art. Many geologists share our enthusiasms; those fine old artists captured their landscapes in a way that strikes a chord with all of us. We look at their paintings and our hearts beat as one with theirs.

We have been longtime members of Cedar Grove: the Thomas Cole Historic Site. It is devoted to the study of this art. Have you been there? Let’s give you a good reason to go. All summer, there will be a fine exhibit of about 20 paintings by Sanford Robinson Gifford. Gifford was one of the leading lights of the Hudson Valley School. We have long admired his paintings so you can imagine how happy we were to hear of this upcoming event.

The paintings on loan are, many of them, from places like the art galleries at Harvard and Yale Universities, along with The Albany Institute of History and Art. Others, however, are from private collections so they are only rarely seen. It has been curated by Dr. Kevin Avery, Senior Research Scholar at the Metropolitan Museum of Art. Dr. Avery has done Gifford exhibits in the past so he is eminently qualified. The exhibit will be housed in the recently reconstructed “New Studio” where Thomas Cole painted during the last few years of his all too brief life. The New Studio has been outfitted to accommodate important exhibits of this sort. In short, this is a major event; so many of you will want to see it.

We, of course, are drawn to all of the scenic landscapes portrayed in the exhibit. But, as geologists we can see things that others miss. We would like to pick two very special paintings and describe them today. The first is entitled “Twilight in the Catskills” and was painted by Gifford in 1861, before he entered service with the Army of the Potomac in the Civil War. The painting had been lost and only in recent years was it rediscovered. It’s a sizable canvas, measuring 27 by 54 inches. It is a view sketched from the eastern end of Kaaterskill Clove. The artist gazed out across the whole Clove and painted it at, of course, twilight. When you look at it, you have to think of Frederic Church’s “Twilight in the Wilderness.” The two paintings share a common color and atmosphere.

Image courtesy of Cedar Grove

You look at the painting and you are looking up the canyon. In the far distance you can see the familiar silhouette of the Clove. In the center you can pick out the location of Haines Falls. To its right is the canyon that descends from Kaaterskill Falls. Further to the right, is the rim of Kaaterskill Clove, a location where today is found the famous Rim Trail.

Would you like to visit the site where Gifford worked? Would you like to go there and see what he saw – perhaps exactly what he saw? Well, we think we can help. The painting shows a ledge of rock in its left center foreground. There is a flow of water running across that ledge and the rest of the clove was painted from that vantage point – the top of a waterfall. We believe that this is the site of the top of Hillyer Ravine, which you can find on the New York/New Jersey trail map, Ninth Edition, Trail Map 141 for the Northeastern Catskills. To get there you must find a legal place to park in Palenville (not easy) and hike up the Long Path Trail. Follow that trail until you get to the top of Hillyer Ravine. It’s an ascent of about 1,500 ft.

We have not been able to do this recently; it has, after all, been winter, but, anyway, we have a better idea. Along the way, you will find a sign pointing you in the direction of something called Poet’s Ledge. The yellow trail descends down a slope and brings you to the ledge. There you will see something very akin to what Gifford saw. See our second image.

View from Poets Ledge, photo by Robert Titus

Compare our photo with his painting; look carefully and you will see a difference. Our photo shows a consistently deep and narrow valley bottom. That is typical of a mountain stream; they are very erosive and always carve deep, narrow valleys. But, look at Gifford’s painting again (our detail, presented as our third image). Gifford has put a floodplain at the bottom of his Kaaterskill Clove and he has added a meandering stream. Few would notice this, but to trained geologists this is a glaring inconsistency. Meandering streams are never found in mountain valleys.

Closeup of “Trilight in the Catskills

We have showed this image to some of our hiking buddies, people who know their ways around the Catskills. They quickly point out how Gifford’s meandering stream reminds them of the upper reaches of Schoharie Creek, just to the west of Plattekill Clove. We agree with them; we had thought the same. So, in the end, we are accusing Sanford Robinson Gifford of cheating! He painted what he wanted to see, not what is actually there! We forgive him; it was for the purpose of creating fine landscape art. And, it that, Gifford succeeded. He and we are still friends.

Image courtesy of Cedar Grove

Let’s pick another very special painting and describe it today. This one was done outside of the Catskills; it’s entitled “The Shawangunk Mountains” and was painted by Gifford in 1864. It’s a small painting, measuring only 9 by 16 inches. It is a view sketched from the very center of the mountains. The artist gazed out across the whole of the southern Shawangunks and painted what he saw.

You look at the painting and you are looking into the very structure of the Shawangunk Mountains. Great ledges of gravelly sandstone tower above the Hudson Valley. These are massively stratified rocks, with horizons leaning back to the right which is the west. The Shawangunks are composed of a relatively pure quartz sandstone and that is a rock which is resistant to all sorts of weathering processes. That’s why those ledges stand out so clearly and that is what must have attracted the artist.

Would you like to visit the site where Gifford worked? Would you like to go there and see what he saw – perhaps exactly what he saw? Well, we think we can help. You will have to visit the Mohonk Mountain House Hotel and find your way to the Sky Top Tower. That won’t be hard; the tower is enormous; it rises high above this lofty part of the Shawangunks. You look south and you should not have much trouble seeing something very akin to what Gifford saw.

Gifford got there years before the hotel was built and, of course, many more years than before the tower. That site lies at the top of a sizable ledge so it must have long attracted the attentions of outdoorsy people. That has probably long included artists. When we were there the last time, we saw some artists sketching right there. But the painting at the exhibit will not be a sketch; it will be one of the classics among those painted by the Hudson River School artists.

We have been associated with Cedar Grove since before it came into being. We have been proud to watch it grow into an art history center of world renown. Every year it attracts preeminent authorities on art history to speak at its winter lecture series. Again we ask, have you been there? Maybe now is the time’

Contact the authors at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist” or log on to their blog site thecatskillgeologist.com.

I have been recently working with the Woodstock Land Conservancy so I know what kinds of good work such civic groups do. I wasn’t surprised to see the Columbia County chapter in the news recently. Maybe you read about the new 47 acre parcel of land they have opened up to the public in Philmont. The centerpiece of this site is High Falls.

High Falls

The falls are well named; they tumble over a precipice of about 150 feet, along a river with the improbable name of Agawamuck Creek. I had not been aware of the site so I snatched my wife and the Professors Titus were soon off to Philmont.

The conservation area is easy to locate off Roxbury Road and there is good parking. The trails are well marked (unless you are color-blind; they only have red and green markers). We followed the green trail out to the overlook with its fine view of High Falls itself. We found a strong flow of water so it was a good view.

But I hadn’t come to see the view; I was there to get a story. As we had hiked the trail we had passed several good outcrops of bedrock. If you take one of these trails here, you will see fine-grained rocks with a dull sheen to them. They are called phyllites. These rocks are metamorphic. That means they had, during some ancient New England mountain building event, been subject to intense heat and pressure. Metamorphism is, quite literally, the cooking of rocks. Sadly, I had not come all the way out to Philmont to do a story on dull looking bedrock; I needed a better story. I will do the rocks another day.

We hiked down to the upper blue trail to the bottom of the canyon. Canyon is the right word for where we were. Very steep slopes, often with rock cliffs, towered above us. That’s were I found my story.

The canyon took me back to the end of the Ice Age, about 14,000 years ago. That was a very, very wet time in the history of Columbia County. It would be fair to describe the whole landscape as soggy from the recently melting glaciers. Agawamuck Creek is a fairly long flow of water today, but back then it must also have been a very powerful, and erosive, stream. That’s when the canyon formed.

If you know anything at all about Niagara Falls, then you will find the story of our little canyon to be a familiar one. Niagara Falls is a rather erosive site. Water flowing over the lip of the falls cascades downward, and is very erosive when it hits bottom. It has carved something called a plunge pool at the bottom. The deep plunge pool undermines the stability of the cliff above and eventually great masses of rock break loose and fall into the pool.

Over long periods of time, in this manner, Niagara Falls has worked its way back, retreating upstream towards Lake Erie. Someday, Niagara will reach Lake Erie, at which point the whole of that great lake will cascade into the St. Lawrence River system. That will be an exciting chapter in the history of the Great Lakes!

Well, my point is that High Falls has, similarly, been working its way back upstream. The canyon below Niagara is miles long; the one here is much shorter, only about a quarter mile in length. So High Falls is a scale model of the greater and far more famous Niagara, complete with a regulation plunge pool. I think that is a notable and that is my story.

But there is a secondary story here; it’s about hydropower. Philmont was once a mill town. The Agawamuck, back in the middle 19th century, was dammed and along with some aqueducts that provided enough hydropower to support a number of mills. We drove up Summit Road to “factory hill” and there we saw a fine old brick mill, just above the falls. It is well-preserved artifact of local 19th century industry. It’s been closed a long time. Perhaps that is unfortunate; we are seeing global climate change associated with the burning of fossil fuels. Maybe the old mill should never have been closed.

A GEOLOGIST never knows when he is about to take a trip into our distant past. It’s just part of the job. I began one of those time travels recently when I was visiting the Livingston mansion “Clermont” on the Hudson. Just north of the visitor’s center I saw a fine Honey Locust tree.

The Honey Locust is certainly not the greatest of trees; there are bigger and prettier ones. Nevertheless, there is something very special about this species. Honey Locusts are “armored” with very dangerous looking spikes. These can be three or four inches long, and often they occur in mean-looking clusters. The biggest of those is found on the lower reaches of the tree’s trunk. Up above, there are plenty more strung out on the lower branches.

Honey locust spikes

Brush up against this tree and you will quickly find out what they are for; they are vicious defense mechanisms. The lower branches hang down, and seem to reach out with their spikes as if intending to do harm. Browsing mammals will soon find out, and long remember, the dangers of trying to eat the foliage of this tree.

But who are these spikes defending against? Your might guess the White-tailed Deer, especially if you are among those who have prized shrubbery in your yard. But White-tailed Deer would hardly be bothered by these spikes. They have slender snouts and they find plenty of space to pick between the spikes. No, locusts have never much worried about deer.

But, if it is not deer, then who? There are no other obvious browsers in today’s woods so why do the trees go to all that trouble of growing those nasty long spikes? Those spikes, also, had to be aimed at something a lot bigger than a deer. And a lot taller too; they reach up to about 15 feet or so above the ground. There is a real problem here; the fact is that there simply are no big creatures in today’s world that threaten our locusts.

But there were some a long time ago. Back at the end of the ice age the Hudson Valley did have a great herbivore which might very well have pestered our Honey Locusts. And it was plenty large enough too. It was the Mastodon.

Modern elephants have a bad reputation for tearing up forests. They love to pull down limbs and they are perfectly capable of stripping bark off the lower trunks of trees as well. In fact elephants can virtually create their own habitat. They destroy so many trees that they break up the forests, creating lots of meadow in between the remaining patches of forest.

That rambunctious behavior creates just exactly the right habitat for Honey Locusts. Locusts like broken forests, preferring to be right on the border between meadow and trees. So, it would seem that evolution had cleverly adapted the locust for life with the Mastodons. These great elephants created the habitat that was just right for locusts. At the same time the spikes protected the locusts from any potential damage from the Mastodons.

And there was more: the Honey Locust seed pods very likely appealed to the Mastodons. Those seed pods hung just above the spikes; the elephants could just reach beyond the spikes, eat the pods and then deposit the seeds elsewhere within their droppings.

All in all the Mastodons and Honey Locusts enjoyed a very fine symbiosis. But then, abruptly, it all ended.

The Mastodons went extinct about 11,000 years ago. The locusts lost the elephants that had helped them so much in reproduction. They have continued to survive to this day, but surely they are not as successful as was once the case. Still, in the end, it is quite the concept to contemplate. These trees and their long spikes vigilantly wait for the elephants that will never ever come again. It is only the ghosts of mastodons that still haunt our forests.

Robert and Johanna Titus will be speaking at Clermont in September. See their website.

It was 2,300 years ago that Plato wrote of a great island, “larger than Libya and Asia taken together.” His island was the fabled Atlantis and it lay out in middle of the Atlantic Ocean, beyond the Straits of Gibraltar. The story went on: fully 9,000 years before Plato’s time Atlantis was a great city state which controlled an empire extending as far east as Italy and Egypt. After fighting and losing a war with the Athenians, Atlantis was consumed by a day and a half of earthquakes and floods. The whole land mass sank into the ocean and it has been lost ever since.

It’s a wonderful story and just the type that we scientists love to debunk. But the word debunk implies ridicule, and when you ridicule a popular myth, you run the risk of appearing arrogant. Now, believe me, arrogance is not exactly unheard of in science, so let’s take a careful look at the story of Atlantis. We will find, as is so often the case, the true story is a lot better than the myth.

You can start by gazing eastward from any prominent high point, preferably the top of the Catskill Front. A lot of geologists have done this. They are looking at Columbia County and the profiles of the Taconic and Berkshire Mountains, but nearly all have pondered the same question: Where did all the rock out there come from? Beneath them, the Catskill Front is made of 17,000 feet of sandstone. That’s only a small part of what is sometimes called the “Appalachian sequence.” The whole sequence consists of sedimentary rocks about 40,000 thousand feet or so thick. It wasn’t always rock, it was once all sediment. Sediment has to come from somewhere and 40,000 feet of it has to come from somewhere big, so you can appreciate the geological curiosity.

James Hall

In the 1840’s James Hall, the great Albany geologist, got very interested in finding where all that sand had come from. He traced these sediments all across North America and soon convinced himself that the thick Appalachian deposits always thinned to the west. It must be, he thought, that if the sediments thinned to the west, then they must have come from a source in the east. Now James Hall had no interests in the myth of Atlantis, but other geologists wondered about that source land. Was this the real Atlantis?

In the late 19th century, Charles Callaway first calculated the total volume of sediment that made up the Appalachian sequence. From this he estimated that there must have once been a source land about the size of Australia out in the North Atlantic. Callaway thought that the weathering and erosion of this source land provided the sediments of the Appalachian sequence and also similar rocks in Europe. Callaway thought that he had come up with the scientific discovery of an ancient lost continent – a real one! He called it “Old Atlantis.” Old indeed, Callaway’s continent was about 400 million years older than Plato’s one.

Callaway’s idea remained popular into the 20th century, but as science progressed, it didn’t hold up all that well. Oceanographers were learning more and more about the floor of the North Atlantic. Surely, they reckoned, if there had once been an Atlantis out there, some remnant would still remain, but none was ever found.

The solution to the “source land problem” came in the late 1960’s and it was a terrific story, much greater than the old myth. Continents and oceans, it turned out, were not eternal. Once there had been no Atlantic Ocean at all, neither was there a North America or Europe. Instead there were great land masses, ancestral to the ones that we are familiar with. Back then, an ancestral Europe was drifting westward and actively colliding with an earlier form of North America. As the two crushed together a great mountain range was thrust up all along the collision zone. Such things do happen and can even be seen today. India is colliding with Asia and the Himalayas are the product of that collision. Our Taconics and Berkshires are part of the 400 million year old ancestral Appalachian system. At their peak they were called the Acadian Mountains and they, not Atlantis, provided the sediments we see today in places like the Catskills.

So the Atlantis of Plato’s myth never did exist. But when we debunk his story, it’s not arrogance, but confidence that science can provide a better story which motivates us. Our story tells of moving and colliding continents. The story speaks of once towering mountain ranges which are no more. It’s a great yarn and one of the most important scientific discoveries of the last century. And to me, the best is that the story comes from the bedrock.

So find the time someday to take a hike up to the top of the Catskill Front and gaze east. Find the Taconics and Berkshires on the distant horizon. That’s Columbia County below and . . . it’s all “Atlantis!” Adds something to the view, doesn’t it?

One of my favorite views in all the Catskills can be seen as you drive south on Rte. 30 on your way towards Grand Gorge. You go around a broad curve in the road and there, off in the distance, is Grand Gorge: not the town but the actual, genuine, authentic gorge itself. If you look in the distance you will see that break in the mountains, a hole in the horizon. This is the gorge; well at least it’s the entrance to that gorge. It’s all just a little bit complex actually. The left, eastern side of the hole in the hills is Irish Mountain. The right, western side is Jump Hill. The two of them combine to create a remarkable landscape form.

What is most interesting about it is that it seems to form an almost perfect semicircle. That may not be an accident. When I geologist sees such a perfect half circle in the landscape, he is very likely to think about the Ice Age and wonder if glaciers had not played a role in this. They very well may have. Let’s learn about what glaciers do in places like this.

When a glacier flows through a relatively narrow valley such as this one, it is likely to modify the landscape. The passing ice grinds away at the bedrock and wears it down. Given enough time – and with geology there is always enough time – the ice will carve a nearly perfect semicircle. It’s always the bottom half of the circle.

There is a reason that this shape develops. The semicircle is the shape that offers the least frictional resistance to the moving ice. The glacier will grind away at the bedrock, shaving off bits and pieces here and there, until it has achieved this semicircle. Then it will have exactly that minimum of frictional drag exerted upon it. It will, in fact, continue to wear away at the bedrock, but that wear serves only to deepen the semicircle, not change it in any other significant way. The ice can continue to flow for years, and decades and centuries. And that is what I was looking at from my Rte. 30 perch. I gazed to the south and, in my mind’s eye, it was many thousands of years ago, and the glaciers were still flowing down the valley.

This glacier is one that I know quite well. It is the Schoharie Creek Valley glacier. It entered the Catskills from the north and flowed south within the confines of the Schoharie Creek Valley. It passed Middleburgh and flowed through Breakabeen. As it approached Grand Gorge it had a choice. One branch of its ice veered off to the east and continued, through Prattsville and on up the Schoharie Creek Valley toward Kaaterskill Clove. It would reach a location named “Mosquito Point” and there it would collide with another glacier coming from the east. That other glacier had entered the Catskills at Kaaterskill Clove and it had flowed through Tannersville and Lexington on towards its collision at Mosquito Point. The collision of two glaciers might seem like an unlikely notion, but they do occur. And that is the option that brought this branch of the valley glacier to an abrupt halt.

But that was only one option. The rest of the Schoharie Creek glacier flowed south through Grand Gorge and on into the East Branch of the Delaware River. That is the flow of ice I had been watching. It was funneled though the Grand Gorge gap in the mountain and it was forced to carve that gap into the form that had so fascinated me. This glacier would continue on to the south. At Margaretville it would veer to the west and continue across what is the Pepacton Reservoir today. It would pass through Downsville and eventually, somewhere to the west, come to a halt, this time without colliding with any other ice.

As you can see, all this is quite a story. The great valleys of the Catskills all had their own valley glaciers. Each of them flowed mostly to the south and each of them carved their valleys into something resembling a semicircle. Had the Ice Age lasted longer in the Catskills, then all of the valleys would be perfect semicircles. This is commonplace in more heavily glaciated landscapes such as those of the Alps, but our Ice Age was just a little too short.

It is only in a few places that we can see those beautiful and striking semicircles, and the one at Grand Gorge is the easiest to visit. Some day let’s climb up into the mountains and see some other semicircles, some much better ones. Reach the author at titusr@hartwick.edu or join his facebook page “The Catskill Geologist.”

I don’t think there are many of us geologists who are not very fond of the Hudson River School of Art. The artists of this “School” created America’s first ever national style of art. Starting right here in the Catskills, during the 1820’s, these landscape artists painted the American wilderness and they got it right. There is something in the spirit of their images that speaks directly to geologists. We feel what they felt when we are out “there.”

Not surprisingly, then, my wife and I have been active members of the Thomas Cole National Historic Site at Cedar Grove, Cole’s home in Catskill. Thomas Cole is widely thought of as a founder of the Hudson River school. Cedar Grove is dedicated to preserving his memory and to honoring the Hudson River artists in general. In its few years of existence Cedar Grove has established itself as a leading, even prestigious center of art scholarship.

Back in 2010 Cedar Grove has opened a new exhibit of paintings by Hudson River artists. That’s not unusual; they have done so every year since 2004, but this one was different. Called “Remember the Ladies,” it is devoted exclusively to the women artists of the Hudson River School. We didn’t want to miss it so we were there the very first day, and it was well worth the visit. About 25 works of art were on display, including some by Cole’s sister, Sarah, and daughter, Emily. But my wife and I best enjoyed one special canvas by Harriet Cany Peale, the second wife of renowned artist Rembrandt Peale.

Mrs. Peale painted in the Catskills in 1858 and her painting Kaaterskill Clove was chosen for the cover of the exhibit‘s 2010 catalog. It is a gem! We thought that we recognized the location where she did this work and resolved to go find the site. We thought it was just below Fawn’s Leap which you must pass by on your way up the clove on highway, Rt. 23A, just west of Palenville. You have to cross two bridges along the way and Fawn’s Leap is a waterfall just above the second bridge.

If you wish to visit where Harriet Peale did her painting the visit on a weekday morning before many people have yet arrived. There is distant parking uphill and downhill; nothing is available right there. Then walk to the bottom of that second bridge, the uphill one, climb down into the clove and then head upstream about 50 yards. There you will find a spot where a mountain cascade comes crashing down from above. Turn around right there and look back downstream. Like magic, you are transported back to 1858 when Harriet Peale was here. You are standing at the very spot where she worked and you can see what she saw – exactly what she saw.

There is a sense of kinship that this sort of experience brings. She and we came here for the same aesthetic reasons. We and Harriet Peale shared exactly the same sights even though we were separated by more than 150 years of history. The Civil War and two world wars have come and gone during this time. The electric light, the plane, the auto and the computer have all been invented, but this location has remained almost exactly as it was. We were just barely able to see the railings of today’s modern bridge and we could hear the passing traffic. But those were the only perceptible changes. In every other sense nothing has been altered.

But our sense of time was so acute here. We saw the great boulders that she painted and we were transported back to the end of the Ice Age. We understand the Ice Age history of Kaaterskill Clove and we know that, back then, a glacier had entered this clove and advanced up, all the way to South Lake. That glacier probably swept these boulders along with it. They are not just picturesque rocks; they are history, Ice Age history. These boulders are called glacial erratics. They were plucked loose somewhere up the Hudson Valley and carried to this location by the advancing ice. After the glacier stopped advancing, it began to melt. As it melted away, these boulders emerged from the old ice. They were left at just this spot by the melting ice, and they have not moved an inch since that time.

And “that time” must have been no later than about 13,000 years ago. Now we stopped thinking of this place as it was during the Civil War; we saw it as it was when the pyramids were being built, and then during time much older than even that. We had developed a new appreciation for the scenery of the Catskills. For more about this summer’s exhibit at Cedar Grove go to http://thomascole.org Find more at http://thecatskillgeologist.com

The Catskills are among the most scenic regions in eastern North America. You already knew that, but one of the reasons is the brick red color of much of our bedrock. Look around and it won’t take long to find, here and there, a handsome outcropping of brick red sandstone and shale. The tint goes well with the green of the summer foliage and makes a picture perfect landscape. But, with so much of that red rock, there must be some cause, a reason for the tinting. There is and this week let’s learn about it.

The best place to begin to account for the color is to learn what causes it. Our brick red is the color of the mineral hematite, an iron oxide. The “hema” part of that refers to blood. Whoever named the mineral must have lived where there weren’t many bricks. He saw the color as that of blood. The is debatable; real blood has a much more intense hue of red than does hematite. If I could have named it, I would have called it “brickite,” a silly name but a more descriptive one.

The iron oxide of hematite has the composition of Fe2O3 and it does, almost always, display a brick red color. In fact it is the mineral that does give bricks their color. The more iron in the brick’s clay to begin with, the more iron oxide that forms as it is fired. But we are not talking about bricks; we are speaking of rock. Hematite does not need to be fired in order to form red rocks. It typically forms in the soils of warm tropical terrestrial environments. When ancient soils are porous and well-aerated, then oxygen from the air can combine with iron to make the iron oxide rich red soils. Warm climates speed things up.

Tropical landscapes, in places such as the Amazon Basin and central Africa, commonly produce a red soil type which has been called a laterite. Other warm landscapes, all over the world, very often have red soils. You have probably heard of the Georgia red clays; these are home-grown versions. Where erosion cuts into any of these soils you can see the red hue.

But, somewhere along the line, I have to get back to the Catskills and why we have so many red rocks here. The answers take us back about 375 million years to a time when our Catskills were a great tropical delta. This was called the Catskill Delta and it was huge: the size of today’s country of Bangladesh which lies upon the Ganges River Delta. Our Catskill Delta lay in a tropical climate. Back then North America had drifted to about 20 degrees south of the equator and that put it squarely within the warmest climate belts.

The Catskill Delta probably had a seasonally rainy climate (some people debate this). One part of the year saw a lot of rain, the rest of the year was dry. The rainy season made our local soils chemically active, but during the dry seasons, they became parched. That’s when air got into them and that is when the iron oxides began to form. And, of course, that is when the soils became red, brick red. The Catskill Delta must have been a land of red soils and today our Catskills are a land of red sandstones and shales.

So, where is the best place to go and see all this? I recommend the drive up Rte. 23 as it approaches Windham from the east. Let’s take in the whole highway. Starting down in Cornwallville, there is a sequence of fine outcrops which extends for three or four miles along the highway. As you drive up the hill you are passing through about 1,500 feet of sedimentary rock, most of it is red. It is a fine sequence which speaks of the great size and thickness of the Catskill Delta deposits and it makes a most scenic want to take a good look, but you will be rewarded by the effort. Their coloration is wondrous. Once you have trained your eye to notice this sort of thing, it is good to keep the image in the back of your mind as you travel the region. Begin to notice how widespread the red strata are. Let each outcrop take you through a window of time, back to the time of the Catskill Delta. It is a great trip. Contact the author at titusr@hartwick.edu Join his facebook page “The Catskill Geologist.”

Once again, this year, I will be doing a Hudson Valley Ramble at Olana (Sat. Sept. 9, 2017, at 10:00 AM). My topic will be “Unplanned views at Olana.” It’s one of this year’s many Hudson Valley rambles. Olana is Frederic Church’s fabled Persian Revival home, perched high atop Church Hill, across the Rip Van Winkle Bridge from Catskill. Church, the great 19th Century Hudson Valley painter, built Olana and designed its 250 acres of landscape. He decorated the property with what are called “planned views.” Those are locations that were landscaped to enhance the scenic views that had already existed. These are grand panoramas of the Hudson River, the Catskills, and the Taconic Mountains. Church devoted all of his considerable artistic skills to developing these views and they are still, more than a century later, wonders to see.

I will take my participants to see several of these planned views, but my focus in not so much in seeing the modern landscape as in viewing images from the distant geological past. We will “see” the glaciers that once overrode this hill and we will descend to the depths of the ocean that, so long ago, swept across this site. It’s a fun trek; I have done it many times and I enjoy it very much.

Olana has a rich and varied geological heritage and there is much to explore. But, at the same time, Olana can keep its geological secrets. One of them has defied all my best efforts. That is the mystery of where is the Olana pothole. Potholes are commonly seen in the bedrock floors of powerful rivers. Swirling currents of water pick up cobbles and gravel and sand and use that material to essentially drill a hole into the bedrock. The drilling continues until, in some cases, perfectly circular potholes, 25 feet or more deep, can be formed. These are commonly seen on many streams in the northeast. Many of them probably date back to the late Ice Age when melting glaciers provided vast quantities of meltwater. There is a well known example of numerous potholes at a location called Moss Island at Little Falls on the Mohawk River. It was designated a National Natural Monument in 1976.

Well, sometime back in the 1870’s, excavations were underway at Olana to recover stone for roads which were then being built. Accounts, written back then, indicate that those diggings occurred at the base of a 75 foot tall cliff of black shale. Workmen encountered a pothole that had lain buried, probably for many thousands of years. They reported the find to geologists and sometime thereafter excavations began in serious. After what must have been a lot of hard digging this pothole turned out to be eight feet wide and 25 feet deep. The walls had a polished appearance to them and, still within the hole, were polished and rounded cobbles, the very ones that had been swirled into the ground so long ago. It was an interesting discovery and several articles about it appeared in the scientific literature. Frederic Church appears to have been nonchalant with it all; he remarked in a letter that he was the proud owner of “a hole in the ground.”

The Olana pothole

Well, all this, of course, was of interest to me. How could it not? But the most pressing and immediate question I had was – where was the pothole? There were no precise directions in the articles about it. One said it was about a half mile from the Hudson River. The other placed it at 300 feet above sea level. Both placed it at the bottom of that 75 foot high cliff of black shale. I got out my map and altimeter and put on my boots and went hunting. But after a few hours of searching all likely places, I had come up empty. I don’t know what happened to the hole. It is always possible that it was destroyed by the quarrying activities of the 1870’s. Nobody else has found it either.

But I had some other problems to deal with. There are no bedrock stream channels here. I needed another explanation for the origin of this pothole. And that solution would take me back to the end of the Ice Age. All this conjures up quite an image of what it might have been like at the Olana site at that time. The Hudson Valley had been filled with the ice of a great glacier, but now it was melting away. I could imagine the remnant ice, abutting well up the slopes of Olana. Masses of water were pouring off of the melting glacier and a lot of that was funneled down a hole in the ice. It was that flow that bored the pothole. For me it’s a whole new “unplanned view” at Olana.